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1Estimation on the response of glaciers in China to the global warming in the 21st century显示文摘Glaciers in China can be categorized into 3 types, i.e. the maritime (temperate) type, sub-continental (sub-polar) type and extreme Continental (polar) type, which take 22%, 46% and 32% of the total existing glacier area (59 406 km2) respectively. Researches indicate that glaciers of the three types show different response patterns to the global warming. Since the Maxima of the Little Ice Age (the 17th century), air temperature has risen at a magnitude of 1.3℃on average and the glacier area decreased corresponds to 20% of the present total glacier area in western China. it is estimated that air temperature rise in the 2030s, 2070s and 2100s will be of the order of 0.4-1.2, 1.2-2.7 and 2.1-4.0 K in western China. With these scenarios, glaciers in China will suffer from further shrinkage by 12%, 28% and 45% by the 2030s, 2070s and 2100s. The uncertainties may account for 30%-67% in 2100 in China.SHI Yafeng & LIU Shiyin Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China 2000Chinese Science Bulletin2000,45,7:71
2Amplitude of climatic changes in Qinghai-Tibetan Plateau显示文摘On the basis of ice core and meteorological data from the Qinghai-Tibetan (Q-l) Plateau, this article focuses on the discussion of the problems related to the sensitivity of temporal and spatial changes of the climate in high-altitude regions, particularly in the Q-T Plateau. The features of abrupt climatic changes of the past 100 ka, 2 000 a and recent years indicate that the amplitude of these changes in the Q-T Plateau was obviously larger than that in low-altitude regions. The scope of temperature change above 6 000 m in the Q-T Plateau between glacial and interglacial stages could reach over 10C℃, but only about 4℃ in low-elevation regions close to sea level. During the last 2 000 a, the amplitude of temperature changes at Guliya (over 6 000 m a.s.l.) in the Q-T Plateau reached 7℃, in comparison with 2℃ in eastern China at low altitude. In the present age, apparent differences of climatic warming have been observed in the Q-T Plateau, indicating that the warming in high-elevation regions isYAO Tandong LIU Xiaodong WANG Ninglian SHI Yafeng 2000Chinese Science Bulletin2000,45,13:47
3Non-canonical regulation of SPL transcription factors by a human OTUBl-like deubiquitinase defines a new plant type rice associated with higher grain yield显示文摘完成增加的谷物生产率长是引起节目的谷物的制服的焦点。ideotype 途径被用来在国际瑞斯研究院并且在中国改进米饭收益潜力。然而,在米饭的收益相关的特点的基因基础仍然保持不清楚。这里,我们显示出那一个主要量的特点地点, qNPT1,通过建筑学由更少 tillers 描绘了的一种新植物类型(NPT ) 的决心的行为,更坚定的灰煤杆和更大的圆锥花序,并且它与相同编码 deubiquitinating 酶到人的 OTUB1。OsOTUB1 的 Downregulation 提高 meristematic 活动,导致在谷物产量的减少的 tiller 数字,增加的谷物数字,提高的谷物重量和米饭的作为结果的增加。不同于人的 OTUB1, OsOTUB1 能劈开连接 K48 、连接 K63 的 polyubiquitin。OsOTUB1 与 E2 结合 ubiquitin 蛋白质 OsUBC13 和 squamosa 倡导者绑定交往像蛋白质的抄写因素 OsSPL14。OsOTUB1 和 OsSPL14 分享普通目标基因,和他们的物理相互作用限制 OsSPL14 的连接 K63 的 ubiquitination (K63Ub ) ,它接着支持 OsSPL14 的 K48Ub 依赖的 proteasomal 降级。相反地, OsOTUB1 的 loss-of-function 与 OsSPL14 的高水平的累积被相关,导致 NPT 建筑学。我们也证明 high-yielding npt1 和 dep1-1 等位基因节节上升为增加在当前是可完成的的上面的米饭收益潜力提供新策略。Shuansuo Wang Kun Wu Qian Qian Qian Liu Qi Li Yajun Pan Yafeng Ye Xueying Liu Jing Wang Jianqing Zhang Shan Li Yuejin Wu Xiangdong Fu 2017Cell Research2017,27,9:33
4Impact of urban expansion on regional temperature change in the Yangtze River Delta显示文摘从 1992 ~ 2003 基于 non-radiance-calibrated DMSP/OLS 夜间光形象,城市的陆地区域统计数据,气象学的数据;陆地地面温度数据由 MODIS 检索了;NOAA/AVHRR 数据,在长江三角洲(YRD ) 的温度的地区性的气候的趋势上的都市化的影响被分析。结论如下:1 ) 在 YRD 从 1992 ~ 2003 有一个重要都市化过程。Nanjing-Zhenjiang-Yangzhou 的四城市簇, Suzhou-Wuxi-Changzhou,上海;Hangzhou 海湾形成一条之字形城市带。在城市带的年平均气温的增加率是从 1991 ~ 2005 的 0.28 0.44 ° C /10a,它比 non-city-belt 的远大。2 ) 在不同季节的地区性的吝啬的气温上的城市的热岛(UHI ) 效果是 summer>autumn>spring>winter。3 ) UHI 紧张;城市的全部的人口对数美满地被相关。4 ) 成为地区性的年平均气温的 UHI 效果从 1961 ~ 2005 增加了 0.072 ° C,它从 1991 ~ 2005 的 0.047 ° C,;年度最大的气温增加了 0.162 ° C,它从 1991 ~ 2005 的 0.083 ° C。所有这些显示当严肃的气候发信号,在从 1991 ~ 2005 的 YRD 的城市的扩大可以被考虑。DU Yin XIE Zhiqing ZENG Yan SHI Yafeng WU Jingang 2007Journal of Geographical Sciences2007,17,4:25
5The mortality of lung cancer attributable to smoking among adults in China and the United States during 1990–2017显示文摘Background:Statistical data on the burden and relevant risk factors of lung cancer are valuable for policy-making.This study aimed to compare the mortality of lung cancer attributable to smoking stratified by sex and age among adults in China and the United States(US).Methods:We extracted age-standardized mortality rates of lung cancer during 1990-2017 using the comparative risk assessment framework of the 2017 Global Burden of Disease study.We performed an age-period-cohort analysis to estimate time trend of lung cancer mortality attributable to smoking.Results:During 1990-2017,the age-standardized mortality rate of lung cancer was increasing in China but decreasing in the US for both sexes.The mortality attributable to smoking in China showed a generally increasing trend,while a continuous decrease was observed in the US.The age-period-cohort analysis showed a similar trend of age effect among adults between China and the US:the mortality substantially increased from the 30-34 to 80-84 age group and subsequently decreased in the 90-94 age group.However,the period effect rapidly increased in Chinese adults during 1990-2017,while it tended to be stable in the US although it was still slightly increasing in women.The cohort effect generally peaked in the earlier cohort born in 1902-1906 in the two countries.Conclusions:During 1990-2017,the lung cancer mortality attributable to smoking and the period effect are generally increasing in Chinese adults;the mortality attributable to smoking is decreasing in the US adults,but the period effect tends to be stable.The rapid aging and prevalence of smoking may intensify the increasing mortality of lung cancer in China.Xiaoxue Liu Yong Yu Minsheng Wang Sumaira Mubarik Fang Wang Yafeng Wang Runtang Meng Chuanhua Yu 2020Cancer Communications2020,40,11:17
6Plant diversity reduces the effect of multiple heavy metal pollution on soil enzyme activities and microbial community structure显示文摘It is unclear whether certain plant species and plant diversity could reduce the impacts of multiple heavy metal pollution on soil microbial structure and soil enzyme activities. Random amplified polymorphic DNA (RAPD) was used to analyze the genetic diversity and microbial similarity in planted and unplanted soil under combined cadmium (Cd) and lead (Pb) pollution. A metal hyper- accumulator, Brassica juncea, and a common plant, Festuca arundinacea Schreb, were used in this research. The results showed that microorganism quantity in planted soil significantly increased, compared with that in unplanted soil with Cd and Pb pollution. The order of microbial community sensitivity in response to Cd and Pb stress was as follows: actinomycetes 〉 bacteria 〉 fungi. Respiration, phosphatase, urease and dehydrogenase activity were significantly inhibited due to Cd and Pb stress. Compared with unplanted soil, planted soils have frequently been reported to have higher rates of microbial activity due to the presence of additional surfaces for microbial colonization and organic compounds released by the plant roots. Two coexisting plants could increase microbe population and the activity of phosphatases, dehydrogenases and, in particular, ureases. Soil enzyme activity was higher in B. juncea phytoremediated soil than in F. arundinacea planted soil in this study. Heavy metal pollution decreased the richness of the soil microbial community, but plant diversity increased DNA sequence diversity and maintained DNA sequence diversity at highlevels. The genetic polymorphism under heavy metal stress was higher in B. juncea phytoremediated soil than in F. arundinacea planted soil.Yang GAO Chiyuan MIAO Jun XIA Liang MAO Yafeng WANG Pei ZHOU 2012Frontiers of Environmental Science & Engineering2012,6,2:14
7High-resolution 3D crustal S-wave velocity structure of the MiddleLower Yangtze River Metallogenic Belt and implications for its deep geodynamic setting显示文摘The Middle-Lower Yangtze River Metallogenic Belt(MLYMB) is an important mineral resource region in China.High-resolution crustal models can provide crucial constraints to understand the ore-forming processes and geodynamic setting in this region. Using ambient seismic noise from 107 permanent and 82 portable stations in the MLYMB and the adjacent area,we present a new high-resolution 3D S-wave velocity model of this region. We first extract 5–50 s Rayleigh wave phase velocity dispersion data by calculating ambient noise cross-correlation functions(CFs) and then use the surface wave direct inversion method to invert the mixed path travel times for the 3D S-wave velocity structure. Checkerboard tests show that the horizontal resolution of the 3D S-wave velocity model is approximately 0.5°–1.0° and that the vertical resolution decreases with increasing noise and depth. Our high-resolution 3D S-wave velocity model reveals:(1) AV-shaped high-velocity zone(HVZ) is located in the lower crust and the uppermost mantle in the study region. The western branch of the HVZ passes through the Jianghan Basin,the Qinling-Dabie orogenic belt and the Nanxiang Basin. The eastern branch, which almost completely covers the main body of the MLYMB, is located near the Tanlu Fault. The low-velocity anomalies between the western and eastern branches are located in the area of the Qinling-Dabie orogenic belt.(2) High-velocity uplifts(HVUs) are common in the crust of the MLYMB,especially in the areas near the Tanlu Fault, the Changjiang Fault and the Yangxin-Changzhou Fault. The intensities of the HVUs gradually weaken from west to east. The V-shaped HVZ in the lower crust and uppermost mantle and the HVUs in the middle and lower crust likely represent cooled mantle intrusive rocks. During the Yanshanian period, fault systems formed in the MLYMB due to the convergence between the South China Plate and the North China Plate, the multiple-direction drifting of the PaleoPacific Plate and its subduction beneath the Eurasian Plate. The dehydration of the cold oceanic crust led to partial melting in the upper mantle. Temperature differences caused strong convection of the upper mantle material that underplated the lower crust and rose to near the surface along the deep fault systems. After mixing with the crustal materials, mineralization processes, such as assimilation and fractional crystallization, occurred in the MLYMB.Song LUO Huajian YAO Qiusheng LI Weitao WANG Kesong WAN Yafeng MENG Bin LIU 2019Science China Earth Sciences2019,62,9:13
8Fabrication,microstructures,and properties of copper matrix composites reinforced by molybdenum-coated carbon nanotubes显示文摘Multiwalled carbon nanotubes(CNTs) were coated by a molybdenum layer using carbonyl thermal decomposition process with a precursor of molybdenum hexacarbonyl.The Mo-coated CNTs(Mo-CNTs) were added into copper powders to fabricate Mo-CNT/Cu composites by means of mechanical milling followed by spark plasma sintering.The Mo-CNTs were uniform dispersion in the Cu matrix when their contents were 2.5 vol.%-7.5 vol.%,while some Mo-CNT clusters were clearly observed at additions of 10.0 vol.%-15.0 vol.% Mo-CNTs in the mixture.The mechanical,electrical,and thermal properties of the Mo-CNT/Cu composites were characterized,and the results showed that the tensile strength and hardness were 2.0 and 2.2 times higher than those of CNT-free specimens,respectively.Moreover,the Mo-CNT/Cu composites exhibited an enhanced thermal conductivity but inferior electrical conductivity compared with sintered pure Cu.The uncoated CNT/Cu composites were fabricated by the similar processes,and the measured tensile strength,hardness,thermal conductivity,and electrical conductivity of the CNT/Cu composites were lower than those of the Mo-CNT/Cu composites.NIE Junhui JIA Chengchang JIA Xian ZHANG Yafeng SHI Na LI Yi 2011Rare Metals2011,30,4:12
9Fault self-repair strategy based on evolvable hardware and reparation balance technology显示文摘In the face of harsh natural environment applications such as earth-orbiting and deep space satellites, underwater sea vehicles, strong electromagnetic interference and temperature stress,the circuits faults appear easily. Circuit faults will inevitably lead to serious losses of availability or impeded mission success without self-repair over the mission duration. Traditional fault-repair methods based on redundant fault-tolerant technique are straightforward to implement, yet their area, power and weight cost can be excessive. Moreover they utilize all plug-in or component level circuits to realize redundant backup, such that their applicability is limited. Hence, a novel selfrepair technology based on evolvable hardware(EHW) and reparation balance technology(RBT) is proposed. Its cost is low, and fault self-repair of various circuits and devices can be realized through dynamic configuration. Making full use of the fault signals, correcting circuit can be found through EHW technique to realize the balance and compensation of the fault output-signals. In this paper, the self-repair model was analyzed which based on EHW and RBT technique, the specific self-repair strategy was studied, the corresponding self-repair circuit fault system was designed, and the typical faults were simulated and analyzed which combined with the actual electronic devices. Simulation results demonstrated that the proposed fault self-repair strategy was feasible. Compared to traditional techniques, fault self-repair based on EHW consumes fewer hardware resources, and the scope of fault self-repair was expanded significantly.Zhang Junbin Cai Jinyan Meng Yafeng Meng Tianzhen 2014Chinese Journal of Aeronautics2014,27,5:10
10Prognostic significance of neutrophil to lymphocyte ratio in patients with hepatocellular carcinoma after transcatheter arterial chemoembolization显示文摘Xu Xinsen Chen Wei Zhang Lingqiang Miao Runchen Zhou Yanyan Wan Yong Dong Yafeng Liu Chang 2014Chinese Medical Journal2014,,24:10
11Surrounding rock control mechanism of deep coal roadways and its application显示文摘Aiming at the surrounding rock control problem of mining and preparation entries in Xingdong mine with large mining depth, and the comprehensive control countermeasures including high pre-stress cable truss system, this study put forward powerful anchor support system and anchor cable adaption technology to surrounding rock deformation. Furthermore, the control measures possess the supporting performance with ‘‘primary rigid-following flexible-new rigid, and primary resistance-following yield-new resistance'', which suits deep roadway surrounding rock control. The mechanical model of truss anchor supporting roof beams was established, and the inverted arch deflection produced by the cable pre-stress with stress increment effect and roof beam deflection were obtained. And then the system working mechanism was illustrated. Finally, the surrounding rock support parameters were determined by means of comprehensive methods, and put into practice. The results show that surrounding rock deformation realized secondary stability after three months. The roadway sides convergence value was less than 245mm, and roof subsidence was less than 124mm. In addition, there was no expansion and renovation during service period.Xie Shengrong Li Erpeng Li Shijun Wang Jinguang He Chongchong Yang Yafeng 2015International Journal of Mining Science and Technology2015,25,3:10
12Living concrete with self-healing function on cracks attributed to inclusion of microorganisms: Theory, technology and engineering applications——A review显示文摘Concrete is the most widely used composite material in civil engineering.Microbial induced calcium carbonate precipitation(MICP)is a green and environmental friendly technology,which has received extensive attention in repair of concrete cracks.This paper introduces the research progress in Southeast University research in past 16 years.In the early stage,MICP technology of urea hydrolyzed by Bacillus pasteurii was mainly investigated to repair the surface cracks and to fill large-size cracks with grouting.However,aiming at the hidden cracks that were difficult for human intervention,a new mineralization route of Bacillus mucilaginosus was proposed,which could repair faster than Bacillus alcalophilus,and the problem of ammonia emission in the repair process of Bacillus pasteurii was also solved.In addition,in order to improve the protection of bacteria and the self-healing efficiency of the later age cracks,the methods of fiber immobilization,carrier uniformly immobilization and core-shell structural immobilization had been compared and studied.The results showed that core-shell structural immobilization had good protection ability and strong designability.What’s more,the paper also summarized the characteristics of spore germination,cell activity,nucleation and biological calcium carbonate in crack zone,and introduced the application experience of microbial self-healing concrete in water conservancy projects and subway stations.QIAN ChunXiang ZHENG TianWen RUI YaFeng 2021Science China(Technological Sciences)2021,64,10:7
13Effects of Target and Distractor Saturations on the Cognitive Performance of an Integrated Display Interface显示文摘Color coding is often used to enhance decision quality in complex man-machine interfaces of integrated display systems. However, people are easily distracted by irrelevant colors and by the numerous data points and complex structures in the interface. Although an increasing number of studies are seriously focusing on the problem of achieving efficient color coding, few are able to determine the effects of target and distractor saturations on cognitive performance. To study the performances of target colors among distractors, a systematic experiment is conducted to assess the influence of high and low saturated targets on cognitive performance, and the affecting extent of different saturated distractors of homogeneous colors on targets. According to the analysis of the reaction time through the non-parametric statistical method, a calculation method of the cognitive performance of each color is proposed. Based on the calculation of the color differences and the accumulation of the reaction times, it is shown that with the different saturated distractors of homogeneous colors, the high saturated yellow targets perform better than the low saturated ones, and the green and blue targets have moderate performances. When searching for a singleton target placed on a black background, the color difference between the target and the distractor should be more than 20ΔE*ab units in the yellow saturation coding, whereas the color difference should be more than 40ΔE*ab units in the blue and green saturation coding. In addition, as regards saturation coding, the influence of the color difference between the target and the background on cognitive performance is greater than that of the color difference between the target and the distractor. Seemingly, the hue attribute determines whether the saturation difference between the target and the distractor affects the cognitive performance. Based on the experimental results, the simulation design of the instrument dials in a flight situation awareness interface is completed and tested. Simulation results show the feasibility of the method of choosing the target and distractor colors, and the proposed research provides the instruction for the color saturation design of the interface.XUE Chengqi LI Jing WANG Haiyan NIU Yafeng 2015Chinese Journal of Mechanical Engineering2015,28,1:7
14Difference between grid connections of large-scale wind power and conventional synchronous generation显示文摘In China, regions with abundant wind energy resources are generally located at the end of power grids. The power grid architecture in these regions is typically not sufficiently strong, and the energy structure is relatively simple. Thus, connecting large-capacity wind power units complicates the peak load regulation and stable operation of the power grids in these regions. Most wind turbines use power electronic converter technology, which affects the safety and stability of the power grid differently compared with conventional synchronous generators. Furthermore, fluctuations in wind power cause fluctuations in the output of wind farms, making it difficult to create and implement suitable power generation plans for wind farms. The generation technology and grid connection scheme for wind power and conventional thermal power generation differ considerably. Moreover, the active and reactive power control abilities of wind turbines are weaker than those of thermal power units, necessitating additional equipment to control wind turbines. Hence, to address the aforementioned issues with large-scale wind power generation, this study analyzes the differences between the grid connection and collection strategies for wind power bases and thermal power plants. Based on this analysis, the differences in the power control modes of wind power and thermal power are further investigated. Finally, the stability of different control modes is analyzed through simulation. The findings can be beneficial for the planning and development of large-scale wind power generation farms.Jie Li Chao Liu Pengfei Zhang Yafeng Wang Jun Rong 2020Global Energy Interconnection2020,3,5:7
15Interactive visualization of 3D lunar model with texture and labels,using Chang'E-1 data显示文摘A lunar model with real texture can be obtained by mapping texture onto the lunar mesh,but the convergence in the polar regions of lunar model is a problem.In this paper,we build a 3D lunar model and solve this problem by texture partitioning and transforming.The whole lunar map is divided into four images and the polar images are transformed to circular textures before mapped to the semi-regular(SR) lunar mesh which is obtained through denoising,triangulating,subdividing and resampling the laser altimetry(LAM) data.Hundreds of lunar labels are classed into three levels and added gradually to the lunar model considering the distance between the viewpoint and the moon center.Through some techniques such as mip-map and view-dependent,the lunar model with textures and labels can be interactively browsed on a personal computer(PC) in real time.DONG YaFeng SUN YanKui TANG ZeSheng 2013Science China(Physics,Mechanics & Astronomy)2013,56,10:6
16Spatio-Temporal Impact of Rural Livelihood Capital on Labor Migra- tion in Panxi, Southwestern Mountainous Region of China显示文摘Labor migration to urban centers is a common phenomenon in the Panxi region of the southwestern mountainous region of China, mainly owing to inadequate livelihood capital in rural areas. Numerous studies have been conducted to explore the relationship between labor migration and its causes, such as individual and family characteristics, but few studies have focused on livelihood capital. This paper examines the impact factors on labor migration employment location selection and duration from a household livelihood capital perspective. A case study of 279 households from 10 villages in the area was carried out in February 2016. We used both qualitative and quantitative methods to analyze the data. On the basis of the 279 questionnaires, the proportion of households with non-labor migration is 48.4%, whereas households with labor migration within a local city and migration across regions account for 28.7% and 22.9%, respectively. Social, financial, and human capitals are the primary factors that influence migrants' employment location choice positively. Among them, social capital has a significant impact on both migration within a local city and across regions; each of the regression coefficients is 1.111 and 1.183. Social, human, and financial capitals also have a positive impact on the duration of labor migration, and similarly, social capital is the highest coefficient with 2.489. However, physical capital only partly impacts labor migration across regions, whereas the impact of labor migration within a local city, and the duration, are not significant. Furthermore, the impact of household natural capital on migration space and time are all negative relationships, especially for labor migration across the regions and duration, with coefficient scores of 4.836 and 3.450, respectively. That is to say, a laborer is inclined to migrate within a local city for a short term, or not migrate at all, if natural capital is abundant. Our analysis results show that household livelihood capital has a strong spatio-temporal impact on labor migration.WAN Jiangjun DENG Wei SONG Xueqian LIU Ying ZHANG Shaoyao SU Yi LU Yafeng 2018Chinese Geographical Science2018,28,1:5
17A SAR Image Segment Method Using Gray Level Reduction Based on Graph in ICA Space显示文摘This paper proposes a new SAR image segmentation method based on graph and gray level reduction in Independent component analysis(ICA) space. Firstly,according to the grayscale information of SAR image, effective use of gray level reduction for initial segmentation can group the pixels with same or similar values to the same homogeneous region, which can address the problem of over-segmentation. Secondly, the features of regions are extracted in ICA space, and then the similarity degree can be calculated by Euclidean distance. The initial regions are merged in fully connected graph based on minimum spanning tree in ICA space. The process of region merging is divided into two phases; the first phrase is merging the different regions with the largest similarity degree, the second will focus on updating the fully connected graph for iteration. Finally, experimental and comparative results on synthetic and real SAR images verify the efficiency of the proposed algorithm.JI Jian LYU Xiaojia YAO Yafeng 2017Chinese Journal of Electronics2017,26,4:5
18Processing of a Novel Zn Alloy Micro-Tube for Biodegradable Vascular Stent Application显示文摘In recent years, zinc based alloys as a new biodegradable metal material aroused intensive interests.However, the processing of Zn alloys micro-tubes(named slender-diameter and thin-walled tubes) is very difficult due to their HCP crystal structure and unfavorable mechanical properties. This study aimed to develop a novel technique to produce micro-tube of Zn alloy with good performance for biodegradable vascular stent application. In the present work, a processing method that combined drilling, cold rolling and optimized drawing was proposed to produce the novel Zn–5Mg–1Fe(wt%) alloy microtubes. The micro-tube with outer diameter of 2.5 mm and thickness of 130 μm was fabricated by this method and its dimension errors are within 10 μm. The micro-tube exhibits a fine and homogeneous microstructure, and the ultimate tensile strength and ductility are more than 220 MPa and 20% respectively. In addition, the micro-tube and stents of Zn alloy exhibit superior in vitro corrosion and expansion performance. It could be concluded that the novel Zn alloy micro-tube fabricated by above method might be a promising candidate material for biodegradable stent.Chang Wang Zhentao Yu Yajun Cui Yafeng Zhang Sen Yu Gongqi Qu Haibo Gong 2016Journal of Materials Science & Technology2016,32,9:5
19Effect of soil management on soil erosion on sloping farmland during crop growth stages under a large-scale rainfall simulation experiment显示文摘Soil erosion on farmland is a critical environmental issue and the main source of sediment in the Yellow River, China. Thus, great efforts have been made to reduce runoff and soil loss by restoring vegetation on abandoned farmland. However, few studies have investigated runoff and soil loss from sloping farmland during crop growth season. The objective of this study was to investigate the effects of soil management on runoff and soil loss on sloping farmland during crop growth season. We tested different soybean growth stages (i.e., seedling stage (R1), initial blossoming stage (R2), full flowering stage (R3), pod bearing stage (R4), and initial filling stage (R5)) and soil management practice (one plot applied hoeing tillage (HT) before each rainfall event, whereas the other received no treatment (NH)) by applying simulated rainfall at an intensity of 80 mm/h. Results showed that runoff and soil loss both decreased and infiltration amount increased in successive soybean growth stages under both treatments. Compared with NH plot, there was less runoff and higher infiltration amount from HT plot. However, soil loss from HT plot was larger than that from NH plot in R1–R3, but lower in R4 and R5. In the early growth stages, hoeing tillage was effective for reducing runoff and enhancing rainfall infiltration. By contrast, hoeing tillage enhanced soil and water conservation during the late growth stages. The total soil loss from HT plot (509.0 g/m^2) was 11.1% higher than that from NH plot (457.9 g/m^2) in R1–R5. However, the infiltration amount from HT plot (313.9 mm) was 18.4% higher than that from NH plot (265.0 mm) and the total runoff volume from HT plot was 49.7% less than that from NH plot. These results indicated that crop vegetation can also act as a type of vegetation cover and play an important role on sloping farmland. Thus, adopting rational soil management in crop planting on sloping farmland can effectively reduce runoff and soil loss, as well as maximize rainwater infiltration during crop growth period.WANG Linhua WANG Yafeng Keesstra SASKIA Cerdà ARTEMI MA Bo WU Faqi 2018Journal of Arid Land2018,10,6:5
20Derivation algebra and automorphism group of generalized topological N = 2 superconformal algebra显示文摘我们决定推导代数学和自守概括拓扑的 N = 组织 2 superconformal 代数学。Hengyun YANG Yafeng YU Tingfu YAO 2013Frontiers of Mathematics in China2013,8,4:4
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